Odor-guided tasks provide a valuable means of investigating basic principles of learning and memory in the rat. However, an olfactory task in which performance depends critically upon an encoding of the associations among stimuli remains to be developed. The current proposal focuses on the development of an odor-guided task in which performance depends upon learning the association between an odor and a specific spatial location. Preliminary training procedures will involve pairing an odor and reinforcement in one of two goal arms, and a different odor and reinforcement in the other goal arm. During testing, rats will be presented with one of the two odors in a start box, and reinforced for entering the goal arm with which that odor had previously been paired. The initial study will involve pilot investigations designed to optimize task parameters. A subsequent study will examine the extent to which performance in this task reflects acquisition of the association between an odorant and a specific spatial location by re-arranging the spatial cues surrounding the apparatus. The final behavioral experiment will examine whether rats are capable of forming odor-place "learning sets". Neuropsychological studies are also proposed to examine the effects of aspiration of entorhinal cortex on acquisition and retention of odor-place associations. Development of this task will not only contribute to our current understanding of olfactory associative learning in the rat, but additionally will provide a paradigm suitable for investigating the neural bases of mammalian associative memory.